Katie Couric has sent a message out to her talk show rivals ahead of the premiere of new show 'Katie' on September 10, 2012. The former CBS Evening News anchor has announced the initial list of guests for her daytime talk show, and it reads like a who's who of Hollywood A-listers.First up will be Jessica Simpson, the former reality star turned millionaire entrepreneur who reportedly signed a contract with Weight Watchers to lose her baby weight. The interview could be a huge scoop, given that Simpson is yet to speak on television about the 'deal'. She has reportedly encountered huge problems losing the weight, and she will discuss the "intense challenge" that she signed up for. Also appearing on the first episode of Katie Couric's talk show will be Sheryl Crow, who wrote and performs the 'Katie' theme song. She may also have plenty to get off her mind too, not least the brain tumor that she was diagnosed with earlier this year. The country star will discuss the harrowing diagnosis "for the first time" as well as describing her relief at discovering it was benign.Other guests for Katie Couric's talk show include Barbra Streisand, Jennifer Lopez -who'll discuss her post-American Idol life - and Demi Lovato, a current judge on THE X FACTOR USA.